Material handling apparatus



March 2o, 1945.

B. M. SMITH MATERIAL HANDLING APPARATUS 2 Sheets-Sheet 1 Filed Jan. 8,1944 FIG. 5

FIG. 4

V, .M non n MH m EN n V M m ms R. M. 2c, E v

March 20,1945. s. M. SMITH 2,372,025

MATERIAL HANDLING APPARATUSr Filed Jan. 8, 1944 l 2 SheetsfSheet 2/NVENTOR au. .9M/TH ATTORNEY Patented Mar. 20, 1 945` y lulvl'lflljfvSTATE s PATENT OFFICE IMATRIAL HANDLING APPARTUS Bruce M. Smith,VHaverhill,A Mass.,`assignor to y Western ElectriciCompany,Incorporated,'New

" Yo'rk,'N. Yi, acorporat ion of NewYork pplicationtlanuary 8,1944,'SerialNo. 517,611 I l fashion `that the orientation of the.work-with respect tothe operating axis or. plane of the tool may beaccuratelyadjusted to correspond to a predetermined relation.. Forexample, inx the manufacture of the slices of crystalline quartz used ina, great variety of yelectrical devices and. apparatus,y the rawmaterial is ordinarily first investigated by optical means tolocatevapproxie' mately in an irregular lump, the crystallographic axes,to determine twinningin lthe molecular structure, and portions.suitable` and,unsuitable for thepurp'ose in hand.i Slabs orbars arethensawed from the material accordingto these deter-l minationsto makeavailablejas much of the suitable material present in. the lump aspossible.

Further crystallographic investigatiorre. g.- with Xfrays, is then madeto `determine accurately the crystallographicl axes ofthis nowhomogeneous material fromwhich .accurately oriented slicesl are to besawed; and such a slab or; bar is' thenl mounted on a saw table forcutting: into bars orv slices. Usually a test piece is cut and lagainstudied by X-ray means, when it may be found.'y

that some minor correction of orientation,Tv say of .the .order of ayfraction of a degree in one or. perhaps two mutuallyperpendiculardirectlons', ist

necessary.

. An. object of the present invention is yto'provide'.`

a work holding apparatusor device for a machine tool', capable ofadjustingthe.,orientation of ai piece of work held in .the device withrespect to; the tool of themachine with. an accuracy `of the*- 40 Withthe above and other objects in vievv,theV y invention may be embodied ina worlrv supporting. device for a machine tool which device comprissfastationary base table,-a tilting table ,pivotable orderof a veryfewminutes of angle.

on the base table about an axis parallel thereto,

a V-block mounted onone of thev said tables and facing the other,`a'planecontact'iace on thee:

comms. (o1. 12s- 12)AM f an embodiment thereof, taken in connection withthe accompanying drawings in whichthe same reference numerals areappliedA to identical in v.the several vfigures and in which Fig.l 1 isa-plan .viewpartly in section and with parts vbroken away ofa workholder embodying the invention; v n

Fig..` 2-is a View thereof in side elevation and partly'in section andincluding a saw not shown in Fig. 1; l

parts FigLB is a viewin end elevation and partly in sectiorrof'theshowing of Fig. 2; Y

Fig. 4l is an"y enlarged section on the line 4 4 ofFig. 1; and w u lFig.5'is anenlarged sectlon'on the line 5--5 offFigfl. Y

.,As herein disclosed, the invention is embodied in a device to `bemounted on the horizontal bed II) of a sawingA machine having a rotarysaw` II carried'on apivotable arm I2 to be movable vertically towardVand from the bed in one .vertical planey only. z' Sawingmachines ofthis character are well known and so only these elements of themachinewhich are pertinentl to the present invention are shown here.` v

Foundationof the deviceof the invention is a rigid horizontal base tableI4 to. be secured on the bed I0 as by bolts I'5. On the base table I4,

a tiltable table I6 is mounted by two identically similarpivot devicesI1 and I8, of which the details :ot Il are shown in Fig. 1 in section.The block I9l is rigidly mounted on the basel table I4 and carries, thepivot pin 20 whose conical' tip enters ai corresponding countersunkrecess inthe block2l secured to the table I6. Thus the tablellisftiltable about the common'axis of the pin 2li-and the correspondingpin `22 (Fig. 2) in the device: I8,which axis is horizontal and parallelto thefjplaneA of vtloesawl I. .'At Vthe right hand side 'of the basetable I4 is an integral extension 24 of the base table upon the uppersideof which is rigidly secured a V- l .block 25 having in the upperface thereof the other ,table and facing the V-groove ofthe V-fL 1block,; a cylindrical spacing element interposed-f.

other -side, and Work the swingv table. I

holding means 'mounted'on betweenand resting against the sides oft'heLQL V-groove on one side and-.the contact facef onthe:4

V-groove. or recess 26whose mutually perpendicular-faces are parallelto`the axis of the pivot pins 2E)k and 22 Aand are hardened and ground toaccuracy; '.Inl this V-groove 2B rests an accuratelyv dimensionedy andcylindrical, hardened adjustment. cylinder 21. f, ,The ,table I6 has anintegral extensionlil, overlying the `extension l24 of the base I4; andin theextension 29 is mountedfa pin shaving ahardened at head 30 Whoseunder face islground--to' be plane and parallel to the .o axis lof thepins 20 and 22,-and which rests'on the cylinderwZI and thereby.'vsupports the table I6.

A screw 3l, having threaded engagement in the base I4 and an enlargedhead 32 bearing on the table le and passing through a correspondingslightly oversize aperture in the table, serves to clamp the right sideo the table down upon the cylinder 21. By means of a collar 33 pinned onthe screw 3i, a short distance below the under side of the tablel, thescrew may be actuated to raise and support the right side of the tablewith the head 38 of the pin 28 clear of the cylinder 21, when the lattermay be exchanged for another like cylinder of different diameter.

A swing table 34 having an integral rearextem sion 35 has the rearextension supported on a spacing member 31 mounted centrally near the yrear edge in the tilting table I6, while front 1 portion of the swingtable. rests on aspacing rail 38 mounted on the tilting table near .andpar!- allel to the front edge thereof. A bridge merrrof the swing table3,4. A pivotal connection, .gens

erally indicated at 40 .and .supported by the bridge 39, connects theswing table to be pivot.- able with respect to the tilting table about avertical axis through the pin 4I `of the devicey 40, the forward portionof the swing table being `thus movable arcuately about this axis on therail 38. A tension vspring 42 connected to a member 43 mounted in theswing table 34 near the iront thereof and toa member 44 mounted lon the-ztilting table i5, serves to keep the 'swing table at all times snuglydown on the guide rail 38.

The swing table 34 alsohas a forward exten.- sion 45 in the left side ofwhich is rigidly mounted a pin 46 whose flat head 41 is hardened Aandground plane. In therighthandportion of the extension 45 is mounted a.pivotable member 48 in which is rotatably but not slidably secured thereduced cylindrically smooth end'of a screw `4tlthreadedthrough a block50 rigidly mounted on l ing table i6. The radius of motion of thecenter.' of the' head 41 about the axis of the pin 4t vle preferablythesame as the radius of motion of the center of the head 30 of the pin28 about the axis of the pins 20 and 22, for then identical variationsin diameter of the cylinders 21 and |21 will produce identical angularshifts of the tables i6 and 34 respectively, and the cylinders may beinterchangeable.

The swing table 34 bears on its upper face at the rear, a rig-idlyattached, transverse rail 53 having on its forward face a horizontalshoulder 54 and an undercut bevel 55. On the forward portion of the sametable is rigidly mounted a ktransverse support rail 56. A removableplate 51 rests o n the rail 56 and shoulder 54 and has a bevelled rearedge 58 matching and abutted against the bevel 55, and a like bevelledfront edge 53. A `block 60 is-rigidly secured on the table 34 in irontof the approximate center of the plate 51 and has mounted on it a.second block 6l having in itsunder parta rectangular slot 62 to houseand guidera rack 63 formed at its forward end with an undercut bevel 84to` serves to hold the lever 61 yieldingly up and the rack withdrawnfrom the plate 51. A heavy handle 10 on the lever serves to urge therack against theplate 51 when the lever is down, to lock the platesecurely and accurately in place against the rear bevel 55. 4A) guiderail 1I is mounted transversely across ftheQnnder side of the plate 51 alittle in front of the rail 53; and this rail 1I abuts Vagainstandslides along a corresponding rail 12 mounted on the upper face of thetable 34, these parts being so dimensioned and located that, when theplate .15.1 is unlocked .from .the bevel .55 by retraction of the rack5.3, the. plate 51 is easily slidable along the bevel 55 Awhileprevented `.from rotation bythe rails 1l and 12.

On the upper faceV of the plate 51 is mounted a work holder clampingdevice :comprising a. transverse rail 1.4 .having an .undercut .bevel1:5 and `a .support shoulder 15,1together with a slablike support 11abutted against the front face of the shoulder 16 and of .equal heighttherewith. A clamp .screw 1B is mounted in a bracket '13 formed on .thesupport 11. These parts are `so proportioned and relatedjthat the Workholder proper 88, which `is essentially'a small rigid metal slabbevelled alongopposite sides, may be clamped, as best shown in Fig. `2,between the bevel 15 and the ,slantingly. disposed screw 18. The work inquestion here may be lthought of as a generally rectangularlyparallelopipedal bar 8l of crystal-l line quartz which is to besawedinto successive transverse slabsby the saw Il. Ordinarily such a bar is.cemented to the ilat upper face of a pad 82 which' is cemented on `theupper face of the work holder proper Y80. The pad 82 is ordinarily arectangle of plate glass interposed between the bar 8l and the holder 80'so that the saw may cut clearthrough the bar and into the padk withoutdamage to the holder proper `80.

On the upper face lof the swing table and atthe right hand side near therear is rigidly secured a pair vof transverse, spaced, parallel railsv83. and 84 extending out to the right from the table. On these rails ismounted a slidableblock 85 formed underneath with a key 86 extendingdown between the rails to prevent the block from turning `on the rails.tically between the rails and through the key and block, has a head 88at the bottom abuttable against the under face of the rails and formedwith an upstariding key portion 89 to ybe slidable between4 the railsand prevent rotation of the bolt. A knurled nut 90: on the upper end ofthe bolt serves to clamp Vthe block in position on the rails. The leftend oi the block 85 is formed with a stop noseai abuttable against thevertical right edge face of -the plate 51.. A. horizontally disposedyoke 82 is pvoted-on the. block 85 with the cross-V bar of the yoke.normally resting on the4 nose 5l and formed with a. stop shoulder 33also abuttahle .against the right hand edge faces of the plate."51.. Theshoulderv 53, overhangs and extends leftward beyond the nose 8| by a`distance equal to the width of the kerf cut by the saw Il I plusthepredeterrnined thickness of lone slice to be-cut'from the bar 3l.'A'handle 94 isprovided A boli-l 81 passing up ver on the yoke tolift'the'shoulder 33 out of engage.. ment withthe'l'alatef512v5 Inoperation,` a quartz crystal bar 8| iscemented onthe pad 82 on the'workholder 80 in as accurate'a predetermined orientation thereon aspractically possible. The doing -cf this is no part of the presentinvention and so' is notv lnecessary to be described in detail here.- Itsuffices to state that by the-customary-methods of doing this, the barwhen in place on the plate 51 as described, is presented to the saw in afashion which will depart from the desired orientation with respectthereto by a matter of not more than thirty minutes of angle withrespect to the axis of the pins 20 and 22 or with respect to the axis ofthe pin .4|, or both.

The clamp nut 90 is loosened and the block 85 I backed away to theright. The handle 61 is raised into the clip 68 to unlock the plate 51by retracting the rack 63. The plate 51 is then slid until the right endof the bar 8| lies under the saw I| (raised at this time) in position tohave a thin slab or slice cut from the end of the bar. The

plate 51 is then clamped in this position by bring- The block 85 is slidto ing down the handle 61. the left until the stop shoulderA 93 abutsagainst the plate 51, and the block is locked in this position by meansof the nut 90, The -saw is then actuated to cut 01T the end slab orslice of the bar, and the saw is raised. The slice cut off is thenexamined by X-ray means and the amount of its departure from the desiredorientation with respect to the crystal structure is determined withrespect to the axis of the pins 20 and 22 and with respect to the axisof the pin 4|.

At this time, itis assumed, the cylinders 21 and |21 are of suchdiameter that the tiltable table I6 is horizontal and at right angles tothe plane of the saw and that the swing table 34 has its center lineparallel to the plane of the saw.

The screw 3| is manipulated to raise the tiltabletable |6 by means ofthe collar 33. The cylinder 21 is interchanged for a similar cylinder ofdiameter differing by the amount needed to correct the angular error ofthe bar 8| about the axis of the pins 20 and 22 with respect to the saw,and the tiltable table I6 is then lockeddown on this cylinder byactuation of the screw 3l. In similar fashion the cylinder |21 isinterchanged for a similar cylinder of such diameter as will cause theswing table 34 to be moved about the pinL 4| to correct the angularerror of the bar 8| about the axis of the pin 4| .with respect to thesaw. Thel bar 8| is then oriented with extreme accuracy in the desiredrelation to the saw; and successive slices cut from the bar by the sawwill have the sawed faces accurately oriented as desired in relation tothe crystal structure of the material of the bar.

After each cut, the plate 51 is unlocked by lifting the handle 61, theshoulder 93 is liftedby the handle 94, the plate is moved over rightwardto abut the nose 9|, and the plate is locked again by lowering thehandle 61. The plate has then been traversed to the right, withoutchange of orientation of the bar with respect to the saw, by the widthof the saw kerf plus the thickness of one slice to be cut, and is readyfor the next' slice to be cut. While this is being done, the nut 90 canbe loosened, the block 85 slid tothe right until the shoulder 93 canagain drop down and .engage against the edge face of the plate 51.

To give some idea of the accuracy of correction attainable by the meansdescribed, let the radius from the axis of the pins 20 and 22 to theaxis of the v-groove' 26`or 'the'radiusfrom the axis of the pin 4| tothe axis' of the V-groove 52 be'9.5 inches" as'in one actual case." IAlso let' the paris beso proportioned 'and arranged thata cylinder 21 or21 of diameterr 0.5000 inch kwill make the tilting tablel I6 horizontalor-v the swing-table 34 have itsjaxis Yparallel to' the plane of thesaw.Thena change in diameter of the cylinderk of 0.00575 inch `rwill causeeither table'to deviate2.5 minutes of angle; and a series of cylindersdiiering in steps of this amount will represent successive changes ofangle of 2.5 minutes up to 30 minutes either way from the median or zeroposition. In this particular instance 0.603555i9.5 tan D where D is theangle desired above or below the median position of the tilting table orto the right or left of the median position of the swing table.

What is claimed is:

1. A work supporting device for a machine tool which device comprises astationary base table, a tilting table pivotable on the base table aboutan axis parallel thereto, a swing table pivotable on the tilting tableabout an axis perpendicular to the axis of pivoting of the tilting tableon the base table, a V-block mounted on one of the two first namedtables and facing the other, a plane contact vface on the other of thetwo rst named tables and facing the V-groove of the V-block, a,cylindrical spacing element interposed between and resting against thesides of the V-groove on one side and the contact face on the otherside, a

second V-block mounted on one of the two last named tables and facingthe other, a second plane contact face on the other of the two lastnamed tables and facing the V-groove of the second V- block, a secondcylindrical spacing element interposed between and resting against thesides of the second V-groove on one side and the second contact face onthe other side, and work holding means mounted on the swing table, incombination with means to press the tilting table to hold the rst namedcontact face and the sides of the first named V-groove firmly againstthe rst named spacing element, and means to press the swing table tohold the second named contact face and the sides of the second namedV-groove rmly against the second named spacing element.

2. A work supporting device for a machine tool which device comprises astationary basetable, a tilting table pivotable on the base table aboutan axis `parallel thereto, a V-block mountedv onv one of the said tablesand facing the other, a planecontact face on the other table and facingthe V-groove of the yV-block, a cylindrical spacing tion with means topress the tilting table to hold l the contact face and the sides of theV-groove rmly against the spacing element.

.3. A work supporting device for a machine tool which device comprises atilting table pivotable about an axis parallel thereto, a swing tablepivotable on the tilting table about an axis perpendicular thereto, aV-block mounted' on one of vthe said tables and facing the other, aplane contact face on the other table and facing the V- groove of theV-block, a cylindrical spacing element interposedbetween and restingagainst the sides of the V-groove on one side 'and the contact face-onthe other sideJ endl-work ,holding-means mountedon the swing taihle. 1

4. A work supporting devicel for a machine :tool which device comprisesa .tilting :table pivotable about 'an 'axis parallel .thereto, ya.'swing table pivota'bie-on the tilting :ta-ble about; an axis.penpendioular thereto, a v-biock .mounted on one of the said tables.and facing the other, 1a. I*plane contact `fece 'on the other tablevanci'ncing the yV- groove of the v-bloekg a. l,cylindrical spacing ele.ment interposed between and resting-against the sides of VtheV V-grooveon one side and the contact face on the .other side, and work holdingmeans mounted on the swing table, in combination with means to press theswing 4tailole to hold `the oontaot face and Ache sides of the V-groovefirmly against the spacing element, y

g BRUCE M. SMITH.

